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Did a volcanic eruption in Alaska impact weather in the Midwest?

Did a volcanic eruption in Alaska impact weather in the Midwest?

The eruption of Mt. Redoubt in Alaska in April, 2009 did not impact weather in the Midwest. Moderate eruptions can lead to cooler temperatures near the mountain, as demonstrated by the Mount St. Helens eruption in Washington on May 18, 1980. The ash plume from Mount St. Helens shrouded Spokane, Wash., for days. The amount of solar energy reaching the surface was reduced by the ash plume, just as a cloud would do. The ash cloud reduced daytime high temperatures by five degrees, when compared to near-by cities unaffected by the ash.

The debris from both Mount St. Helens and Mt. Redoubt remained mostly in the troposphere, and had no global effect. Much larger volcanoes can inject material into the stratosphere, where it can reflect solar radiation back to space for years. Mt. Tambora in Indonesia erupted in April 1815, spreading debris across the globe for more than a year, causing the “year without a summer” in 1816. In New England snow fell in June and frost occurred in July and August. In Europe, the cold and wet weather contributed to a disastrous harvest as crops rotted in the field.

Mt. Tambora’s eruption did have at least one benefit, however. In summer, 1816, a group of friends vacationed in Switzerland, but the cold wet weather kept them indoors, so they decided to see who could tell the best ghost story. The winner was Mary Shelly. Her ghost story, Frankenstein, was published in 1818.

Steven A. Ackerman and Jonathan Martin are professors in the Department of Atmospheric and Oceanic Sciences at UW-Madison, are guests on the Larry Meiller‘s WHA-AM radio show the last Monday of each month at 11:45 a.m.